The present invention relates to a cannula having an electrode for detecting an intraortic electrocardiographic signal which can be used for example, in an artificial heart apparatus, a pulsatile artificial heart-lung apparatus, a pulsatile bypass pump apparatus, a vein-vein bypass apparatus, PTCA, etc. for synchronous operation with the pulsation of a natural heart.
It is important for an artificial heart which is connected in parallel to a natural heart to pump blood with a pulsation synchronous to a natural heartbeat. It is well known in the art that an electrocardiogram is provided by comparing voltage differences between plural electrodes stuck on the body. However, such electric signals may have some drawbacks.
Such electric signals include both electrocardiographic signals and electromyographic signals and accordingly, there may be a disturbance of the electrocardiogram caused by movement of the patient. The voltage level of such an electrocardiographic signal may be low and therefore the S/N ratio is low. Thus, detection of the electric signals may be difficult. Signal components may vary in accordance with the positions of electrodes and therefore, some skill may be required to place the electrodes on a patient's body.